- // A register defined by an implicit_def can be liveout the def BB and livein
- // to a use BB. Add it to the livein set of the use BB's.
- if (!isPhys && cur.empty()) {
- if (MachineInstr *DefMI = mri_->getVRegDef(cur.reg)) {
- assert(DefMI->getOpcode() == TargetInstrInfo::IMPLICIT_DEF);
- MachineBasicBlock *DefMBB = DefMI->getParent();
- SmallPtrSet<MachineBasicBlock*, 4> Seen;
- Seen.insert(DefMBB);
- for (MachineRegisterInfo::reg_iterator ri = mri_->reg_begin(cur.reg),
- re = mri_->reg_end(); ri != re; ++ri) {
- MachineInstr *UseMI = &*ri;
- MachineBasicBlock *UseMBB = UseMI->getParent();
- if (Seen.insert(UseMBB)) {
- assert(TargetRegisterInfo::isPhysicalRegister(Reg) &&
- "Adding a virtual register to livein set?");
- UseMBB->addLiveIn(Reg);
- }
- }
- }
- }